I read somewhere on these forums that it rarely helps, and if you want to get more explosiveness from your punches do something that more mimics the exploseveness of a punch, like barebell chest presses.

I honestly dont like using them cause I have never seena difference in my training with them.

Itll help build some small amount of muscle, I found my shoulders to be a little stronger.

And even though your punches seem faster afterwards, its more because your arms were used to punching with 2 lbs, now they have nothing in them when you drop the weights, thus making them feel lighter with less stress on the muscle. Not because your muscles seem a littles stronger. Its more physics than anything.

Maybe in the long long run it helps :/

Personally, I just found its better to do other exercises.

Even though everyone at the gym asks why I dont use them when everyone is doing shadowboxing.

Shadowboxing with weights will put too much stress on your joints and will cause tear in tendons over a long period of time.

Now you might see some muscles develop, in another 10 years you'll notice your elbow joints being painful.

Punching with weights on your wrists, is stupid imo.

If you want resistance while punching, you could use those err... ok... I'm going brain-dead again. You know those elastic bands? Tie them to a wall behind you, and then try punching.

Another exercise you could try to is to punch away on the bag until you lift it up into the air. Keep it there, if you let it fall down to it's original place. Start over. Keep it up in the air for 1 minute.

-Taison out

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I got two fists.. Don't make me use my head as well!

Think about where the resistance is being created/increased if you punch holding weight. As the arm extends, the extra weight acts as downforce, this means that the shoulder muscles have to divert energy from extending the arm, into holding it up at the appropriate height. This compromises neuromuscular coordination with mixed messages, and actually slows down and weakens your punches.

As Ed suggests, a weighted vest will be of benefit, as this focusses the extra power needed to generate the strike through the greater resistance firmly in the legs, hips and core. The arm is the least important thing in a good punch.